Abstract
<jats:title>Abstract</jats:title><jats:p>A growing body of evidence suggests that excessive Zn<jats:sup>2+</jats:sup> release plays a key role in inducing neuronal death during central nervous system injury. However, the possible cytotoxicity of extracellular Zn<jats:sup>2+</jats:sup> to oligodendrocyte lineage cells remains unknown. Employing cultures of rat oligodendrocyte progenitor cells (OPC), we report here that OPC are vulnerable to increased extracellular Zn<jats:sup>2+</jats:sup> levels and that pyruvate limits Zn<jats:sup>2+</jats:sup>‐induced OPC death. Zn<jats:sup>2+</jats:sup>‐induced concentration‐dependent (pEC<jats:sub>50</jats:sub> = −4.1 ± 0.1) OPC death, which was insensitive to both α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid receptor (Evans Blue) and <jats:sc>l</jats:sc>‐type Ca<jats:sup>2+</jats:sup> channel (nicardipine) inhibition. Neither kainate nor nicardipine influenced OPC <jats:sup>65</jats:sup>Zn<jats:sup>2+</jats:sup> accumulation, in contrast with the Zn<jats:sup>2+</jats:sup> ionophore, pyrithione. Cytotoxic extracellular Zn<jats:sup>2+</jats:sup> concentrations failed to increase OPC reactive oxygen species production and the antioxidant reagents, trolox, N,N′‐diphenyl‐1,4‐phenylenediamine and N‐tert‐butyl‐α‐phenylnitrone did not afford significant protection from Zn<jats:sup>2+</jats:sup> insults. The apoptotic inducer staurosporine induced the appearance of known apoptotic markers [pyknotic nuclei and caspase‐3 specific (120 kDa) α‐fodrin cleavage fragment], events not reproduced with Zn<jats:sup>2+</jats:sup> insults. Zn<jats:sup>2+</jats:sup> insults were also insensitive to the pan‐caspase inhibitor Z‐VAD‐fmk. However, pyruvate afforded significant OPC protection from lethal Zn<jats:sup>2+</jats:sup> insults. We conclude that cultured OPC are vulnerable to Zn<jats:sup>2+</jats:sup> insults, via a nonoxidative stress and noncaspase‐3‐based mechanism, involving Zn<jats:sup>2+</jats:sup> inhibition of OPC glycolysis.</jats:p>
Original language | English |
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Pages (from-to) | 287-294 |
Number of pages | 0 |
Journal | European Journal of Neuroscience |
Volume | 19 |
Issue number | 2 |
DOIs | |
Publication status | Published - Jan 2004 |